Variable interest entity settlement value of third party interests.

No definition available.

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- Definition

Variable interest entity settlement value of third party interests including reserves.

+ References

No definition available.

+ Details

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- Definition

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

The amount deducted from an entities' taxes, reflecting a percentage of an amount invested in certain assets spread over the useful life of those assets; includes deferred investment tax credits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(h))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph h

-Article 7

+ Details

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (bb)

-URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5710-111685

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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Variable Interest Entities - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
LIHTC Funds [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Carrying Amount of Assets, Consolidated VIEs	$ 1	$ 1	$ 1
Settlement value of third-party interests, reserves	4
LIHTC Funds [Member] \| Minimum [Member]
Variable Interest Entity [Line Items]
Settlement value of third-party interests, approximately	0
LIHTC Funds [Member] \| Maximum [Member]
Variable Interest Entity [Line Items]
Settlement value of third-party interests, approximately	4
LIHTC Funds [Member] \| Investments [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Carrying Amount of Assets, Consolidated VIEs	1	1	$ 1
LIHTC Investments [Member]
Variable Interest Entity [Line Items]
Tax credit of investment	99	84
Investment in LIHTC	1,000	926
LIHTC Investments [Member] \| Investments [Member]
Variable Interest Entity [Line Items]
Amortization of investment	$ 85	$ 72